The invention concerns a mixer tap cartridge with adjustable flowrate limitation.
A mixer tap cartridge is an assembly adapted to be placed in a mixer tap body between two water inlet passages, respectively for cold water and for hot water, and a mixed water outlet passage that is generally in a portion projecting from the tap body that in practice is called the spout.
The cartridge adjusts the flowrates of the cold water and the hot water to be mixed. In other words, from the point of view of the user, the cartridge adjusts the overall flowrate and the proportion of hot and cold water, i.e. the temperature at the overall flowrate.
To this end the cartridge in practice includes a fixed disk, advantageously of ceramic, and a mobile disk pressed against the fixed disk and able to move over the latter in translation and in rotation. The fixed disk includes at least two openings respectively communicating with the hot and cold water inlet passages and the mobile disk has a geometry adapted to close off each of the openings in the fixed disk to a greater or lesser degree, according to its position and its orientation.
The position and the orientation of the mobile disk relative to the fixed disk are in principle controlled by a single lever projecting out of the cartridge and coupled to an operating member such as a handle mobile relative to the body of the tap and accessible to a user.
In practice this lever (and the same goes for the operating member) has a reference axis that is fixed relative to the body of the cartridge and the inclination of the lever relative to this axis determines the overall flowrate while its angular position about this axis determines the relative proportions of hot and cold water.
The cartridge generally includes a cartridge body and, within the latter, a bush (or collar) adapted to turn about a first axis of the body, preferably coincident with the aforementioned reference axis of the lever, and the lever passes through this bush to which it is hinged about a transverse pin fixed relative to the bush.
The bush defines a limited range of relative angular movement of the lever about the transverse pin, between a minimal (in practice nil) flowrate configuration corresponding to a minimal inclination relative to the reference axis and a maximal flowrate configuration corresponding to a maximal inclination of the lever relative to the reference axis.
Evidently, for a given cartridge including a given bush and a given lever, this range of relative movement is in principle fixed.
The need has arisen to be able to adjust the maximum flowrate allowed by a cartridge according to its use.
Solutions have already been put forward to enable such adjustment.
A first solution consists in providing a longitudinally mobile bearing portion on the lever; this is an attached part having a ramp inclined to the longitudinal axis of the lever; according to the longitudinal position of this part on the lever, the portion of the ramp that abuts a corresponding portion of the bush is closer to or farther away from the longitudinal axis of the lever, whence a greater or lesser maximal inclination of the lever relative to its reference axis; this solution is relatively complex since it is necessary to provide a reliable means of attachment of the attached part to the exterior surface of the lever (it must not be possible for it to become detached), which would appear at first sight to be incompatible with easy adjustment of the longitudinal position of the attached part.
A second solution appears to consist in providing a bearing portion on the bush that is mobile either radially or axially, for example due to the action of a screw-nut system. However, these solutions have the drawback of necessitating a specific arrangement of the bush compared to its conventional configuration, which makes the bush more fragile. The possibility of the bush breaking and the seal between the disks deteriorating, which would cause leaks, cannot be tolerated. Furthermore, the position of the mobile abutment can in practice only be adjusted when the cartridge is removed from the tap body, or even when the bush is removed from the cartridge. Thus it can sometimes be necessary to perform many mounting/demounting operations of the cartridge into/out of the body before the correct adjustment of the maximal flowrate is obtained.
An object of the invention is to alleviate these drawbacks by using an extreme flowrate (in practice maximum flowrate) adjustment stop that is easy to install in a reliable manner, at the latest possible stage in the manufacture of the component parts of the cartridge, without making the bush more fragile, and the position of which can be easily adjusted, preferably even when the cartridge is in place in a tap body.